The present invention relates to a heater and/or an air conditioner with air-side temperature adjustment for a motor vehicle and in particular, a motor vehicle air-side temperature adjustment having an air flow emerging from a mixing chamber at least into one floor air duct and into one defrost air duct with a "blow-out" air temperature which can be varied by adjusting at least one air-mix flap. A warm-air duct directed through a heat exchanger and a fresh-air or recirculating-air duct separated from the heat exchanger discharge on the intake side are connected to the mixing chamber. A conventional type heater and/or air conditioner is disclosed in EP-A1-0 419 707.
In a known heater and/or air conditioner with air-side temperature adjustment means, the air is provided as either fresh air or as circulating air by a blower fan either directly or via a flat heat exchanger into a mixing chamber. The outlet side of the mixing chamber is connected to at least one floor air duct and one defrost air duct. An air-mix flap pivoted in the mixing chamber can be tilted to intermediate positions between a position completely prohibiting fresh air from being admitted on the one hand, and a position completely prohibiting warm air from being admitted on the other hand, such that either fresh air or recirculating air which is completely unaffected by the heat exchanger, or air tempered by the admixture of a larger or smaller air component delivered via the heat exchanger, may be supplied to the air ducts connected to the outlet of the mixing chamber with a correspondingly higher "blow-out" air temperature. By dividing the mixing chamber into two adjacent halves, each with its own air-mix flap, a separate left-side or right-side temperature adjustment was achieved. The air ducts connected to the outlet side of this type of mixing chamber can only lead, possibly via multiple bends, to the discharge nozzles in the floor area, near the windshield, or to the side windows. The bends in the air duct result in a relatively high air-side contact resistance.
DE-C2-39 24 317 discloses a heater and/or air conditioner for motor vehicles with water-side temperature adjustment having a heat exchanger practically bent in a U-shape to such an extent that fresh air or recirculating air discharged by a blower fan arranged centrally inside the heat exchanger is delivered radially through the heat exchanger into floor and defrost air ducts for the right or left side of the vehicle. The blown air can also be discharged through the open area remaining between the sides of the U-shaped heat exchanger to a fresh-air chamber preferably connected to nozzles of the median plane of the motor vehicle (e.g., located at the center of the dashboard). One refinement provides additional connecting ducts situated in the vicinity of the upper side of the U-shaped heat exchanger able to be closed by single flaps so that air may be run from the warm-air side to the fresh-air chamber to temper the cold air in the median plane.
U.S. Pat. No. 2,334,915 discloses a seat heater, in which an axial fan wheel, arranged inside a partial-ring-shaped heat exchanger, delivers fresh air and recirculating air, respectively, depending on the position of an arrangement of several intake-side flaps, in a variable mixture ratio via the heat exchanger to the ambient space.
The object of the present invention is to provide a heater and/or air conditioner controlled on the air side which, with a compact and simple construction, prevents the fresh-air chambers from being undesirably tempered by the heat exchanger and which permits the air-side contact resistance to be decreased, particularly with a separate left-side or right-side temperature adjustment.